Association between physical activity, participation in Physical Education classes, and social isolation in adolescents

Objective: To analyze the association between physical activity, participation in Physical Education classes, and indicators of social isolation among adolescents. Methods: This was an epidemiological study based on secondary analysis of data from a representative sample of students (14-19 years) from public high schools (n=4,207). Data were collected through the questionnaire Global School-based Student Health Survey. The independent variables were the level of physical activity and enrollment in Physical Education classes, while the dependent variables were two indicators of social isolation (feeling of loneliness and having few friends). Descriptive and inferential procedures were used in the statistical analysis. Results: Most of the adolescents were classified as insufficiently active (65.1%) and reported not attending Physical Education classes (64.9%). Approximately two in each ten participants reported feeling of loneliness (15.8%) and, in addition, about one in each five adolescents reported have only one friend (19.5%). In the bivariate analysis, a significantly lower proportion of individuals reporting social isolation was observed among adolescents who referred higher enrollment in Physical Education classes. After adjustment for confounding variables, binary logistic regression showed that attending Physical Education classes was identified as a protective factor in relation to the indicator of social isolation 'having few friends,' but only for girls. Conclusions: It was concluded that participation in Physical Education classes is associated with reduced social isolation among female adolescents. (C) 2015 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.